At Kyoto University, Drosophila have been subcultured in the dark for 1954 generations for 61 years from 1500, and are called "dark flies".The appearance is the same as that of a normal wild-type fly, but it is said to be adapted to the darkness because it leaves offspring in a dark place in a predominant manner over the wild-type fly.A phenomenon in which one base of the genome sequence is different is called a single nucleotide polymorphism (SNP), which is considered to be a factor that creates diversity.In previous research, the entire genome sequence of dark flies was determined, and about 1 Identified 1 SNPs.However, it was unclear which SNPs were involved in the dark adaptation.

This time, we have succeeded a mixed population of dark flies and wild-type flies in the light and dark places.It was expected that repeated passages would mix both genomes and increase the frequency of SNPs involved in dark adaptation in the dark population.When the frequency change of dark fly SNP was examined by genome analysis, about 6% of the genomic sequences were selected in the dark, and 84 genes were identified as candidate genes involved in dark adaptation.It contained genes related to the sense of smell and circadian rhythm.

In addition to the results of listing candidate genes involved in environmental adaptation of "dark flies", an experimental example of narrowing down the genomic sequences involved in environmental adaptation by subculturing mixed populations in different environments was shown for research on environmental adaptation. Proposed a new methodology.In the future, we would like to identify adaptive genes by integrating the results of dark fly gene expression analysis and genome analysis, and to verify the effects of dark fly SNPs by introducing dark fly SNPs into the wild-type fly genome. ... apparently ...